b 1. Field of the Invention
The invention relates to a high-resolution charge-coupled solid-state imaging device of an interline transfer type.
2. Description of the Background Art
A conventional solid-state imaging device has a vertical resolution conforming to, e.g., 525 scanning lines specified by standard television systems such as the NTSC (National Television System Committee) system.
However, to perform high-definition imaging applicable to higher-definition television systems, such vertical resolution of the conventional solid-state imaging device is not sufficient, and thus development of a solid-state imaging device with a larger number of pixels has been called for.
To meet such a demand with an interline transfer type charge-coupled solid-state imaging device whose vertical and horizontal resolutions are improved, the number of photodiodes, each of which corresponds to a pixel, must be increased. This in turn decreases the aperture of each photodiode, thereby causing the problem of impairing its light receiving sensitivity. If the width of each vertical charge transfer path for transferring charges is narrowed to maintain light receiving sensitivity, the charge transfer capacity must be reduced, thereby resulting in blooming and reduction of dynamic range.